Chelsea's preparations for their potentially critical Premier League game against Wigan have been severely undermined after Petr Cech and Demba Ba were rendered highly doubtful for the game at Stamford Bridge after suffering injuries in the weekend defeat at Newcastle.

Ba suffered a badly broken nose after being inadvertently kicked in the face by Fabricio Coloccini, with Chelsea waiting for the extensive swelling around the striker's eyes to recede before they can properly assess the extent of the damage before Saturday's match. Cech broke a little finger after making contact with an opponent as he attempted to punch a ball away during the first half on Tyneside and has been ruled out of the Czech Republic's friendly with Turkey.

Chelsea's medical staff will make their own judgment of the fracture when the goalkeeper returns to the training ground on Wednesday – players and management staff have been granted 72 hours off after a draining recent schedule – but the 30-year-old suggested in an interview conducted in the Czech press that he may even miss next week's Europa League tie against Sparta Prague.

"I punched the ball and the head of one of Newcastle players at the same time," said Cech. "I thought it was nothing but went for an x-ray just in case. However, it showed there was a fracture. [Involvement in the first leg in Prague] will depend on whether we find a solution where it would not threaten my health and, at the same time, I would be able to perform adequately. If I were unable to give 100%, I would not play. With the splint I have now it would not be possible at all."

The pair's absence would constitute a blow even on Saturday, in a fixture Chelsea would normally expect to win but one which has been rendered far more awkward given the team's recent travails and with pressure mounting on the interim first-team manager, Rafael Benítez. Chelsea may be four points clear of fifth place as they target Champions League qualification, but they won only one of their past six matches in all competitions and the stand-in manager's position will come under huge scrutiny if that place in the top four appears to be in doubt. The Spaniard, whose contract expires at the end of the season, retains the backing of the hierarchy at present but there is anxiety at the team's form, and Saturday's match must be won to allay immediate concerns.

David Luiz, who has been absent with ankle trouble, should be fit to return for that fixture to offer Benítez an option at centre-half or in the middle of midfield. Eden Hazard, who has served his three-game suspension for his altercation with a ball boy at Swansea, will also return to contention.